Networks may be logically subdivided into Virtual Private Networks (VPNs), Virtual Local Area Networks (VLANs), or another logical subnets, network areas, or domains. For example, a VLAN may be further logically subdivided by a user into a plurality of user VLANs or VPNs. Provider Backbone Bridging (PBB) and/or Provider Link State Bridging (PLSB) may be used to separate an enterprise domain from one or more user domains by using an additional MAC (Media Access Control) address header in an Ethernet Frame. PLSB may enable the use of a link state protocol to improve the sharing of layer 2 information. However, layer 2 VPNs may terminate on a User Network Interface (UNI) port. Routing among these user VPNs may require actual port to port connections. Establishing such port to port connections may require connecting UNI ports of a VPN to an external router. Such routing may be difficult to increase in scale and manage as the number of user VPNs increases.
In another approach to provide routing connectivity between user VPNs, an external routing function may process translation between a layer 2 VPN and a PLSB layer 2 VPN. This approach may also require an additional connection to an external router to handle translation between a layer 2 VPN and a PLSB layer 2 VPN for multiple layer 2 ELSE VPNs terminating on a VLAN UNI port. Thus, this approach may also require external routing and may add additional overhead and complexity.
In view of the foregoing, it may be understood that there may be significant problems and shortcomings associated with current technologies for routing data between network areas.